As we have mentioned in class, the key issue here is your audience. Your message would be absolutely useless if you haven´t analyzed your listeners before, or have no idea about them.

While searching for some articles about this, I came across this one in particular. It's a whole chapter from the "Public Speaking Handbook", published by Longman (http://www.ablongman.com/).

Although it's 29 pages long, it's really worth reading it.

Here's the link to the pdf file containing the information.

See you in class!